Bahrain, the 14th province of Iran declares it's independence from mainland. Bahrain had been a part of Iran since the Achaemenid empire. After the fall of the Sassanid dynasty in the 7th century, Arab migration to the region accelerated. During the Deylamian dynasty, Bahrain was under the Fars governor's supervision which kept their Iranian characteristics until the Portuguese occupied the region. The Safavids succeeded in expeling the Portuguese and created naval units to protect the region against foreigners. The British colonists used the opportunity associated with the Qajar dynasty's weaknesses to divide the country, thus installed some migrants as Caliphate in Bahrain. Still Iran always kept good ties with Bahrain although some efforts during Reza Shah and Mosaddegh administration to reclaim Bahrain were futile. Mohammad Reza Shah finally became the person who had the honor of giving Bahrain up; therefore leaving the Shiite and Iranian inhabitants alone in a bad situation similar to that of Iraq during the Baath regime.